I'm currently using a 300d with a Canon 75-300 USM for my surfing shots. As you can see below its not bad but at full stretch it struggles and loses its sharpness.
Just what are my choices to get closer to the action?
Can i use a teleconverter with a 300d? And is this a wise thing to do considering the lense i currently have? If not what do you guys and girls recommend as being the next step up?
Thanks in advance
Mealers

You have a number of available options to get closer to the action. First, you could use a teleconverter with your existing lens, but remember that a TC also multiplies your widest aperture, so a 2x would give you a 600mm lens but an aperture of 11.2. You would have to use manual focus and with that little amount of light entering the lens it may prove difficult. It would also limit your options regarding lighting conditions. Also, sharpness will diminish when you add a TC and if you're already not happy with the sharpness of that lens at 300, you'll really be unhappy with a 2x converter attached.

There are a number of longer lenses available that would better suit your needs depending on your budget. We have a considerable number of users here that have and like the Sigma 50-500mm lens. The Canon 100-400 L is also a good possible choice as is the Canon 400L. I believe Tamron has another Di lens either newly released or on the horizon to be released shortly with a focal length of 200-500 f/5.6-6.3. In any case, any of these lenses are going to set you back from $1000-1400 or so. You might want to take a look at these, then ask specific questions regarding those lenses that interest you.